Electro-mechanical shaft positioning device



Oct. 31, 1961 c. COHEN EEQAL 3,006,198

ELECTRO-MECHANICAL SHAFT POSITIONING DEVICE Filed March 6, 1959 2Sheets-Sheet 1 INVENTORS. CHARLES L. c0/-/ DONAL F LUSE, JR.

z/ 4W X/MM A TTORNE Y Oct. 31, 1961 c. 1.. COHEN ETAL 3,006,198

ELECTRO-MECHANICAL SHAFT POSITIONING DEVICE Filed March 6, 1959 2Sheets-Sheet 2 INVENTORS. Cl-MRLES L. COHEN DONAL F LUSE, JR.

iz/WM A TTORNE Y United States Patent 3,006,198 ELECTRO-MECHANICAL SHAFTPOSITIONING DEVICE Charles L. Cohen and Donal F. Luse, Jr., Hyattsville,Md., assignors to ACF Industries, Incorporated, New

York, N.Y., a corporation of New Jersey Filed Mar. 6, 1959, Ser. No.797,804 2 Claims. (Cl. 7410.2)

This invention relates to electro-mechanical shaft positioning devicesand, more particularly, to devices operable either automatically ormanually for rapidly tuning radio apparatus and the like to selectedpositions corresponding to selected frequencies.

An object of the invention is to provide an electromechanical shaftpositioning device operable either automatically or manually in eitherdirection for rapidly and accurately tuning a radio apparatus or thelike to preselected positions or frequencies.

Another object of the invention is to provide an electromechanical shaftpositioning device embodying means for pro-selecting the shaft positionor frequencies to be obtained during operation of the device.

Another object of the invention is to provide an electromechanical shaftpositioning device embodying means for pre-selecting the shaft positionsor frequencies to be obtained during operation of the device.

A further object of the invention is to provide a tuning device in whicha tuning shaft is rotatable in either direction by an electric motorconnected thereto through a link and lever drive mechanism, and afriction clutch interposed between said motor and mechanism.

Another object of the invention is to provide a tuning device embodyinga pair of adjustable stop members to limit movement of the drivemechanism in either direction.

Another object of the invention is to provide a tuning device which isrelatively simple and inexpensive to manufacture and reliable in use.

The invention embodies other novel features, details of construction andarrangement of parts which are hereinafter set forth in thespecification and claims and illustrated in the accompanying drawings,forming part thereof, wherein:

FIG. 1 is a front elevation illustrating an electromechanical shaftpositioning device embodying features of the invention.

FIG. 2 is a side elevation showing the device.

FIG. 3 is a section taken along the line 3-3 of FIG. 1.

Referring now to the drawings for a better understanding of theinvention, the electro-mechanical shaft positioning device is shown ascomprising a housing 5 having a tuning shaft 6 journaled thereon forturning a variable radio condenser 7 or the like. A dial 8 is secured tothe shaft '6 and provided with calibrations 9 for registry with apointer -11 on the housing to indicate, for example, selected radiofrequencies.

A lever 12 is journaled on the shaft 6 and pivotally connected at 13 toone end of an adjustable link 14 which is pivotally connected at itsother end at 16 to an operating lever 17 secured on a drive shaft 18.The drive shaft 18 is journaled in bearings 19 and 21 provided on amotor support 22 secured to the housing 5. A reversible electric motor23 is mounted on the support 22 and acts through a friction clutch 24 todrive the shaft 18.

The friction clutch 24, of conventional construction, is shown ascomprising a driving plate 26 secured to the motor shaft 27, a drivenplate 28 secured to the shaft 1-8, a friction plate 29, and a resilientmember 31. The driving plate 26 and friction plate 29 are intercon- Y,3,006,198 Patented Oct. 31, 1961 nected for common rotational movementby means of a driving pin 32, and the friction plate is frictionallyengaged against the driven plate 28 by means of the resilient member 31.

Rotational movement of the drive shaft 18 is limited by adjustable stopmembers 33 and 34 mounted on the motor support 22 for abuttingengagement against opposite sides of the lever 17. The stop members 33and 34 are shown as comprising circular disks formed with eccentricbores to receive bolts 36 and 37, respectively, extending throughapertures in the motor support 22.

The dial 8 and lever 12 are locked together for common rotationalmovement by means of a screw 38 threaded into the lever and acting toclamp the dial rim between a pair of washers 39 mounted on the screw.

In operation, the motor 23 is energized to rotate the shaft 18 in aclockwise direction until the lever 17 moves into abutting engagementagainst the stop member 33. By reversing the rotation of the motor, theshaft 18 is rotated in a counter-clockwise direction until the lever 17is moved into abutting engagement against the stop member 34. By thusrotating the shaft 18, the lever 17 acts through the link 14, lever 12,and dial 8 to position the shaft -6 in pre-selected positions. To adjustthe device to obtain different shaft positions, the stop members 33 and34 may be moved toward or away from each other and/or the dial 8 may bemoved relative to the lever 12.

Having described a preferred embodiment of the present invention, it isto be understood that although specific terms and examples are employed,they are used in a generic and descriptive sense and not for purposes oflimitation; the scope of the invention being set forth in the followingclaims.

What is claimed is:

1. An electromechanical shaft positioning device comprising a reversibleelectric motor, a clutch operatively connected to said electric motor, adriving lever operatively connected to said clutch for rotation ineither of two directions, adjustable stop members mounted in therotational path of said driving lever for limiting movement thereof, adriven shaft movable in either of two directions, a driven leverjournalled on said driven shaft, means mounted on said driven shaft formanually rotating the same to a preset position, releasable lock meansmounted on said driven lever to secure said driven shaft to said drivenlever at a preset position, and a link interconnecting said drivinglever and said driven lever for proportionally rotating said drivenshaft in response to rotation of said electric motor.

2. An electromechanical shaft positioning device for tuning a variableradio condenser to preset positions comprising reversible electricmotive means, a friction clutch operatively connected to said electricmotive means, a driving lever operatively connected to said frictionclutch for rotation in either of two directions, a pair of preset stopmembers mounted in the rotational path of said driving lever forlimiting rotational movement thereof, a driven shaft operativelyconnected to said variable condenser and movable in either of twodirections, indicating means mounted on said driven shaft, a drivenlever journailed on said driven shaft, means fixed to said shaft formanually rotating the same, releasable lock means mounted on said drivenlever to secure said indicating means and said driven shaft to saiddriven lever at a presetposition of said variable condenser, and a linkinterconnecting said driving lever and said driven lever forproportionally rotating said indicating means, said driven shaft andsaid variable condenser in response to rotation of said electric motivemeans.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Nelsen et a1. Aug. 29, 1939 4 Olson Apr.19, 1949 Unk et a1. Nov. 4, 1952 Deibel July 10, 1956 Karlsruher Oct.20, 1959 Hellyer Nov. 24, 1959

